i hope this helps tin lizzie owners:
the tin lizzie 18 SL is a mechanical machine. a regular repairman can fix it. it has no computer parts unless you upgrade it. it can be lifted right off the trolley and removed from the frame (it weighs a TON) and wrapped up and good to go. i clean mine out myself the same way i do my computerized machines. that is, remove the dust and lint, take out the bobbin casing, etc. and i have never had to do anything else.
i'm lucky to have a repairman who comes to the house and does a thorough cleaning at the same time as my other machines, about once every 16 months. he removes it as i said and works on an old desk. he takes it further apart than i do and cleans deeper, but so far, no problems with the timing or anything. after i got the motion down, i found i preferred the manual stitching better that the regulated, but that's me.
there's a yahoo! group that anyone can join specifically for the tin lizzie. you can lurk and read questions and answers or sign up and be able to ask your own questions. you can request answers by email, which i prefer because they can be more detailed and you can ask further questions and have back and forth discussions without hogging the forum. when i first got mine i learned a lot from that group.
http://help.yahoo.com/l/us/yahoo/groups/original/